change the speed of audio in real time without changing pitch
SampleSumo's time stretching technology can be used to change the tempo/speed of an audio source without altering the pitch of the material. This can be done in real time or offline. The time stretching factor may also vary over time and can be changed while processing.
The library handles both mono and stereo audio sources and has various options to balance the CPU usage and quality of the stretched audio. The API for the library is very simple and requires very little time to integrate the technology into your project.
The TS library is available as a C/C++ library with documentation, development guide and extensive example code. We currently support Windows, macOS and iOS (let us know if you would like to use it on other platforms).
Contact us for more details, pricing info or an evaluation license to get you started.
This example is a fixed-factor (fixed percentage) time stretch.
Sound example taken from Biodiesel Family by snowflake
20% slower | 10% slower | original | 10% faster | 20% faster |
This example is a fixed-factor (fixed percentage) time stretch.
Sound example taken from Ophelia's Song by Musetta.
20% slower | 10% slower | original | 10% faster | 20% faster |
In this example, we used time-varying time stretching to change the temporal feeling of a loop. By varying the time stretching factor over the duration of one beat we can change the loop to have a "shuffled" feeling to it.
Sound example taken from Rezzo_4.wav by Flick3r.
original | variation 1 | variation 2 |